Technology of VR

1
Technology of VR

• Group Members
• Azura Mat Salim
• Fadlynna Ilyani Zulkarim
• Chieng Chin Yi
• Ernie Darlina Taib
• Norkhairul Wahab

2
VRML

• Virtual Reality Modelling Language (VRML)
• International standard file format
• Describing interactive 3D multimedia on the
• Internet.
• VRML 1.0 created based on the Open
• Inventor file format.
• Capabilities were further extended with the
  release
• of VRML 2.0
• VRML97 replaced VRML 2.0 as the ISO standard

3
VRML Features

• VRML defines most common attributes found
• in 3D applications
• Transformation, texture mapping viewpoints and
• materials
• Able to compose objects for VRML worlds using a
• generic text editor
• Can be used for defining VRML documents and / or
  
• as a file interchange format
• Support for various scripting languages (e.g.
• JavaScript)

4
VRML Features

• Uses a hierarchical scene graph in
• describing 3D objects and worlds
• VRML 2.0 design enables a prototyping mechanism,
  
• allows encapsulation and promotes reusability
  of
• scene graphs
• VRML browser is required to view VRML objects
  and
• worlds.

5
VRML Applications

• Commonly used in creating virtual worlds
• Architectural walkthroughs
• Scientific visualization
• Sntertainment and industrial designs
• Lacks the networking and database protocols to
• create true multi-user interactive 3D worlds
• Technology of multi-user worlds requires the
• integration of VRML with other languages such
  as
• Java
• 2 key elements in creating a virtual world
• A text editor or build tools
• A VRML browser to view the world

6
Java3D

• Full-featured 3D graphics API
• Implementation is layered on top of native
  low-level
• rendering APIs, namely OpenGL and Direct3D
• Part of the Java Media family of APIs
• High-level programming language
• Based on Java
• Shields users from low-level rendering details
  e.g.
• hardware acceleration.
• Supports high levels of optimization and
  multiprocessor
• rendering

7
Java3D

• Easily create virtual worlds that are immersive
  and
• even interactive.
• Lets users to deal with lighting, texture
  mapping and
• various other behaviors.
• Powerful yet easily mastered graphics
  capabilities.
• Able to support applications that operate on a
  variety
• of output devices
• Portability and networking capabilities
• May run on different operating systems,
  different
• low-level graphics APIs or different graphics
• hardware.

8
Java3D Features

• Scene graph programming model
• Java 3D rendering control
• Scalability
• Convenience and Utility Classes

9
Java3D In A Nutshell

• Basically the Java programming interface for
  interactive 3D
• graphics.
• Provides developers and users platform-independen
  t, high-
• performance applications and applets.
• Greatly simplifies programming as opposed to
  other low-
• level APIs such as OpenGL and DirectX.
• An optional package that is installed on top of
  Java 2.

10
MPEG-4

• ISO/IEC standard developed by MPEG (Moving
• Picture Experts Group)
• Formal ISO/IEC designation is ISO/IEC 14496
• Became an International Standard in 1999.
• MPEG-4 builds on the proven success of three
  fields
• Digital television
• Interactive graphics applications (synthetic
  content)
• Interactive multimedia (World Wide Web,
  distribution of
• and access to content)

11
MPEG-4 Features

• For authors
• Enables the production of content that has
  greater reusability, greater flexibility
• digital television
• animated graphics
• World Wide Web (WWW) pages and their extensions.
• Better manage and protect content owner rights.

12
MPEG-4 Features

• For network service providers
• Offers transparent information
• Can be interpreted and translated into the
  appropriate
• native signaling messages of each network with
  the help
• of relevant standards bodies.
• Provides a generic QoS descriptor for different
  MPEG-4
• media.
• The exact translations from the QoS parameters
  set for
• each media to the network are beyond the scope
  of
• MPEG-4 and are left to network providers.
• Signaling of the MPEG-4 media QoS descriptors
  end-to-
• end enables transport optimization in
  heterogeneous
• networks.

13
MPEG-4 Features

• For end users
• MPEG-4 brings higher levels of interaction with
• content, within the limits set by the author
• Brings multimedia to new networks, including
  those
• employing relatively low bit rate, and mobile
  ones

14
MPEG-4 Goals

• To avoid a multitude of proprietary,
  non-interworking formats and players by providing
  standardized ways to
• Represent units of aural, visual or audiovisual
  content,
• called "media objects
• Describe the composition of these objects to
  create
• compound media objects that form audiovisual
  scenes
• Multiplex and synchronize the data associated
  with media
• objects, so that they can be transported over
  network
• channels
• Interact with the audiovisual scene generated at
  the
• receivers end.

15
MPEG-4 Implementation

• Allows for robust communication over limited
  rate
• wireless channels, useful for e.g. mobile
  videophones
• and space communication
• Allow the transmission and storage of
  high-quality
• video suitable for the studio and other very
• demanding content creation applications
• Interactive web-based video
• Encode video captures with a hand-held camera
• Games market

16
Overview of Open Inventor TM

• Presents a programming model based on a 3D scene
  database that dramatically simplifies graphics
  programming.
• Based on OpenGL indirectly taking the advantage
  of OpenGL such as platform/window-systems
  independent.
• Simplifies the software development process and
  allows very rapid development of graphics
  applications.

17
Design Architecture

• Open Inventor includes-
• 3D scene database shapes, property, group,
  engine, and sensor object.
• Node kits mechanism for creating pre-built
  grouping of inventor nodes.
• Manipulators interaction tools for user such as
  handle box and trackball.
• Inventor component library to provide some high
  level interactivity task.
• Component library is window-system dependent but
  is available for most platforms thus maintaining
  the common look-and-feel for applications across
  platforms.
• OpenGL is used for all shading, lighting, and
  drawing via the GLX extension provided by OpenGL.

18
Design Architecture (contd)

• New nodes and behaviors can be added by the
  programmer in a number of very easy ways.
• Dynamic shared objects (DSO) allows any new node
  to be available for any Inventor application for
  reading/rendering.

19
Other Languages for VR

• AC3D
• AC3D is popular 3D object/scene modeler available
  for Linux, Windows 95/NT, and SGI.
• It outputs POV-Ray, VRML (1 and 2), RenderMan,
  Dive, Massive and other format.
• Benefits
• Multi platform program - AC3D file format
  compatible across platforms.
• Built-in fast OpenGL 3D renderer with adjustable
  field-of-view - instantly see results of your
  actions in 3D. Spin the model or switch into
  'walk mode' for Quake-style control.
• 24-bit color palette with adjustable diffuse
  ambient emissive shininess and transparency

20
Other Languages for VR(contd)

• Minimal Reality.
• Set of software tools for the production of
  virtual reality systems and other forms of
  three-dimensional user interfaces.
• Consists of a set of subroutine libraries, device
  drivers, support programs and a language for
  describing geometry and behavior.
• Benefits
• Applications developed using MR will run at most
  MR sites with little or no modification to the
  source code.
• Complete source code is provided with the MR
  distribution (Open source).
• The MR toolkit was designed to be easy to extend.

21
Other Languages for VR(contd)

• TCL/TK
• Visual Tcl is a high-quality application
  development environment for UNIX, Windows,
  Macintosh, and AS400 platforms.
• Features
• Extensible widget and geometry manager support.
• Create compound widgets and widget libraries.
• Visual Tcl features new ready-to-use widgets
  combo box, multicolumn list box, progress bar.
• Predefined compounds available including scrolled
  text, scrolled list box, scrolled canvas,
  horizontal and vertical splitters.

22
Other Languages for VR(contd)

• X3D
• Next-generation open standard for 3D on the web.
• Extensible standard that can easily be supported
  by content creation tools, proprietary browsers,
  and other 3D applications.
• Replaces VRML, but also provides compatibility
  with existing VRML content and browsers.
• Benefits
• There are significant commercial and open-source
  movements for advancing X3D.
• X3D content is modular and reusable.
• X3D supports optional XML encoding for tight
  integration with other Web technologies.

23
Summary